— How many of you have solved the math problem?—________, the math problem is far too difficult for us to work out..
The old man was seen _______ in the park at 7:00 a.m. yesterday.
______ a host of the show is really ___________.
--- Where is your mother? --- She has ______ to Sichuan on business. She has ______ there four times recently.
It ____ over 10 years since my grandpa _______.
The food in this shop ______ good and ______ very well.